1. Field of the Invention
The invention relates to a method and cutting tool and track system useful for cutting through a workpiece having flat or arcuate surfaces.
2. Discussion of Related Art
Numerous portable cutting tools are known in the art of cutting workpieces having flat and curved surfaces. In relation to cutting pipes, portable pipe cutting tools are typically used in the field where the use of a fixed machining tool is not appropriate or possible. Types of conventional pipe cutting tools include portable lathes such as one described in U.S. Pat. No. 4,418,591 or roller cutter modules such as one described in U.S. Pat. No. 5,515,756. Generally, conventional portable pipe cutting tools include a rotary tool head carrying a fixed or rotary cutting tool that is driven in rotation about an axis while otherwise fixedly supported relative to the pipe by clamps or a mandrel. Normally, a single-point tool is fed around and into the pipe repeatedly to remove a small amount of material each pass until the pipe is cut through, which in the case of a thick wall may consume a considerable amount of time.
In conventional pipe cutting tools, it is a challenge to locate and support the cutting tool so that smooth and true machining operations can be performed at high tool loadings, while maintaining bearing assemblies free of gross contamination such as chips generated during the machining operation. High radial and thrust loads are encountered during high speed machining of thick walled pipe made of stainless steel and other hard materials, and such machining loads require the use of massive and complicated tool support assemblies.
Known pipe cutting tools are typically designed to fit pipe sizes within certain ranges. Furthermore, such tools may be limited to cutting only pipes and therefore lack the versatility to perform cutting operations on flat or arcuate surfaces.
Another known approach to cutting workpieces, especially larger pieces, involves the use of track guidance systems that comprise a drive track for guiding and feeding a cutting tool along the surface of a workpiece. Conventional track systems known in the art include large structural track systems encircling and rigidly secured to a workpiece such as one a described in U.S. Pat. No. 4,297,061, track systems that are connected to structural members not supported directly onto a workpiece such as one described in U.S. Pat. No. 5,403,133 or lightweight track systems such as those described in U.S. Pat. Nos. 4,570,542 and 6,494,307 that are directly attached to a workpiece with magnets or suctions cups. It has been found, however, that conventional cutting tool and track systems are either not easily and quickly attachable or removable from a workpiece or insufficiently robust to withstand the rigors of high speed, high load machining.
Therefore, it is desirable to provide a metal cutting tool and track guidance system that is highly portable, while sufficiently robust to withstand high machining loads and configured to be rigidly secured to a workpiece. It is also desirable to provide a cutting tool and guidance track system that is capable of being quickly and easily attached and removed from a workpiece having flat as well as curved surfaces. It is further desirable to provide a cutting tool and track guidance system which can accommodate a variety of workpieces whether tubular, flat or arcuate, and precisely cut through such workpieces in a minimal amount of time.